By Jan TenBruggencate
Advertiser Columnist

Scan any Windward beach, and you'll find plastic bottles, bottle caps and various shards and chunks of plastic.

If you get down on your hands and knees, you'll see bits of multi-colored plastic the size of grains of sand. With a microscope, you'd see even smaller pieces.

The bigger pieces are often flaking and brittle, suggesting the plastic may be breaking down. But the folks at the Algalita Marine Research Foundation say it is in fact breaking up. Plastic marine debris ages in the sun and breaks into smaller pieces, but the pieces survive.

Algalita came through Hawai'i late this summer with its research vessel, the Aguita, a sailing catamaran that hauled fine-meshed nets through the ocean to gauge the amount of plastic.

Capt. Charles Moore said some of the most disturbing data was collected in the central Pacific gyre — an area in the middle of the wind and current regimes of the North Pacific where plastics and other marine debris accumulate.

Moore said researchers found various kinds of marine life swimming with the plastic. They weighed the plastic found in their nets, then the plankton found with it. There was a pound of plankton for every six pounds of plastic.

"Practically every place that we sampled had these plastic fragments in it," Moore said.

Hawai'i environmental activist Michael Bailey sailed with Aguita through the Northwestern Hawaiian Islands. He said the foundation was concerned about the possible effects of large amounts of plastic on human health, particularly the little-studied area of hormone disruption from chemicals associated with plastics.

Bailey expressed concern about "the growing environmental crisis pertaining to very small plastic particles, some less than one micron (one millionth of a meter) in size, which are easily consumed by wildlife and fish, and which could also affect human beings who eat fish that are contaminated with plastics."

Even larger pieces are problematic. Fish may mistake tiny tan-colored plastic bits for the shrimp-like krill that form one of the ocean's major food sources. Nurdles, plastic pellets before processing, resemble fish eggs and may be eaten by birds and fish. Seabirds such as albatross snap up floating cigarette lighters and other colorful bits of plastic and feed them to their chicks, which are found dead on nesting islands with their bellies filled with the stuff.

Algalita Foundation calls floating plastic "a poison pill."

Jan TenBruggencate is The Advertiser's Kaua'i bureau chief and its science and environment writer. You can reach him at (808) 245-3074 or jant@honoluluadvertiser.com.